UB55 multivariate analysis: hi-lo contrast, group-level

1 intro

Purpose:

1. Preliminary look at hi/lo multivariate contrast (cross-validated euclidean) in each task.
2. Preliminary qualitative comparison of effects of prewhitening and pattern standardization on multivariate contrast.

Notes on analyses:

Target TRs:

• Axcpt: 7, 8, 9
• Cuedts: 9, 10
• Stern: 11, 12
• Stroop: 2, 3, 4

Contrasts (cross-validated euclidean):

• Axcpt: \(\text{BY} - \text{BX}\)
• Cuedts: \((\text{InConSwitch} + \text{InConRepeat} - \text{ConSwitch} - \text{ConRepeat})/2\)
• Stern: \(\text{LL5RN} - \text{LL5NN}\)
• Stroop: \((\text{PC50InCon} + \text{biasInCon} - \text{PC50Con} - \text{biasCon})/2\)

2 Network-level

Estimates are first averaged across parcels within network per subject. Group-level stats and plots are then displayed at the network-level.

2.1 curves

2.1.1 HiLo contrasts

2.1.2 HiLo contrast t-stats (group)

3 parcel-level

3.1 curves

3.1.1 counts of significant effects per TR

3.1.2 runwise univariate ROIs

3.1.3 largest 20 ROIs

3.2 maps (target TRs)

Unthresholded and thresholded t-statistics. Threshold at fdr-corrected p-value (across all parcels) of 0.05.

3.2.1 Axcpt

3.2.1.1 unstand white

3.2.1.2 stand white

3.2.1.3 unstand unwhite

3.2.1.4 stand unwhite

3.2.2 Cuedts

3.2.2.1 unstand white

3.2.2.2 stand white

3.2.2.3 unstand unwhite

3.2.2.4 stand unwhite

3.2.3 Stern

3.2.3.1 unstand white

3.2.3.2 stand white

3.2.3.3 unstand unwhite

3.2.3.4 stand unwhite

3.2.4 Stroop

3.2.4.1 unstand white

3.2.4.2 stand white

3.2.4.3 unstand unwhite

3.2.4.4 stand unwhite